Method of reeling-off silk cocoons



Patented Nov. 23, 1926.

Bnnnnnn ncnwnor ZURICH, SWITZERLAND.

irnrr on or Jeannine-err SILK cocoons.

No Drawing. Application f led December 27, 1923, Serial 1Y0. 653,081, and in Austria January 24, 1823.

According to the present inventipn the cocoons are immersed in a bath consisting f n l a ine s lu i n .1 e 'elu io' of a kaline earths (either in a caustic state or in combination with weak acids), the temperature of which is the same as the ordinary eem empe t of e r bu ma l o e b le r z n P int The tim of mme n d pends on h sa esmenon and the temperature of the According to the composition of the bath used albumiet are f rm d wi th st e th ween threads, hisk l eminet ar aee e in cold water, but soluble hot water. The bast is thereby rendered soft and sticky, the threads of a number ofcocoons treated at the'same'time adhere together and the reeling-off of the cocoon threads, from which the bast has not been removed, then proceeds easily cold water-or in a moist state in the air. I

The scouring of the reeled-off silk (Gregs or twisted silk) can be subsequently effected in a simple manner before dyeing by a treatment in hot water in contradistinction to the usual reeling-off methods, in which the scouring is effected bythe use of alkaline baths, soap, soap-suds or the like.

The treatment of cocoons according to the present invention may be carried out for instance in the following manner (1) Preferably the cocoons are first immersed in a cold bath consisting of neutral, alkaline or acid salts, mineral or organic acids or oils emulsified with or dissolved in alcohol or other or sulphonated oils, according to the properties which it is desired to impart to the reeled-off threads (Gregs or twisted silk). The object of this treatment is to weaken the direct effect on the cocoon threads of the alkaline solutions or the solu tions of alkaline earths used subsequently, by making the action indirect only. For preliminary baths of this kind substances may for instance be used, such as sodium acetate, sodium formats, zinc acetate, ammonium sulphate, magnesium sulphate, sodium chloride, zinc chloride, hydrochloric acid, acetic acid, lactic acid, formic acid, oleic acids and the like. The cocoons can be left immersed, for instance for 15 minutes or for a number of hours, according to the degree of concentration of this preliminary bath, while vacuum or pressure may be used for accelerating the action.

By this preliminary treatment the pupae of the silk-worms in the cocoons are killed and, when this has takenplace, the cocoons washed or neutralized if necessary, after which they are immersed in a bath, which, as stated above, consists of an alkaline solution or a solution of alkali'ne earths, in a caustic state or in combination with weak wide s h: a eer ee i xide e ie d or the like, For this purposefor, instance a solution of caustic soda of 0-3 Be. or more, at a temperature of 25 C. or less, even below 0,is used. The time of immersion is 1 to 30 minutes, but can be extended for several hours according to the degree of concentration and the temperature of the bath.

Fatty oils or soap may be added to this bath, which substances are suitable for reducing or increasing the action of the bath. 1

In order to ensure that the solution should penetrate into all the hollow spaces within the cocoons, the work may be carried out at a pressure below or above that of the atmosphere. The bast fibres of the cocoon will thereby be softened right down to the innermost layers and the subsequent reeling-off of the cocoon can be effected without any difficulty. The threads of a number of cocoons will adhere to each other perfectly.

It may be remarked that the treatment described in paragraph (2) may be carried out alone, that is, without the preliminary treatment described in paragraph (1).

(3) The cocoons are thereupon bruised either in cold water or while they are still in the bath just described, in which they have been treated, so that the ends of the cocoons may be found and the cocoons may be reeled-off in cold water, without scouring them. The scouring can be effected subsequently in the finished Gregs or in the twisted thread by a simple treatment in boiling water, the reeled-off silk being for instance immersed for about 30 minutes in water at 100 C.

For increasing the lustre, the flexibility,

l the elasticity and the toughness of the threads, substances, such as oil, glycerine, gluocose or the like may be added to the baths, in which the cocoons have been treated.

Finally, the cocoons may be dyed before being reeled-off by immersing them, after they have passed through the chemical treatment described above, in a suitable dyeing bath of the required shade. They are left in this bath until the dye has penetrated into all the hollow spaces, vacuum or pressure being used if required. The silk dyed in this manner has not been scoured and can be softened during the dyeing of the cocoons by the addition of for instance oils or the like. The cocoons are thereupon rinsed in cold water or a slightly acidulated bath, after which the reeling-off and spinning may be proceeded with. According to the way the spinning is carried out dyed Gregs or twisted silk is obtained in this manner.

What I claim is 1. A method of treating silk worm cocoons without degumming consisting in first treating the cocoons in a preliminary bath of mainly a cold watery solution of at least one substance containing an acid radical, continuing this preliminary bath until the silk worm pupae are killed, and then t1'eat ing the cocoons in a second water bath containing an alkaline reacting substance for at least a minute at a temperature not exceeding 0., then reeling off the cocoons at an ordinary temperature, without the employment of hot water, whereby the degumming can subsequently take place in ordinary hot water, without the addition of soap.

2. A method of treating silk cocoons as claimed in claim 1 in which the treatment in the baths is conducted at a pressure less than atmospheric pressure.

3. A method of treating silk cocoons as claimed in claim 1 having the added step of washing and drying the cocoons and storing them away for a period of time between the first and second baths.

4. A method of treating silk cocoons as claimed in claim 1 in which the baths contain substances such as glycerine, glucose and the like, capable of increasing the elasticity, suppleness and toughness of the silk filaments of the threads.

In testimony whereof I have aflixed my signature.

BERNARD LOEWE. 

